EIGRP MD5 Authentication

EIGRP supports MD5 authentication in Classic Mode, and both MD5 and SHA-256 in Named Mode. For MD5 authentication in both Classic and Named modes, the key chain is defined globally.



R1(config)#
!
key chain EIGRP-MD5
 key 1
   key-string MYPASS
!
interface Loopback0
 ip address 1.1.1.1 255.255.255.0
!
interface FastEthernet0/0
 ip address 12.1.1.1 255.255.255.0
 ip authentication mode eigrp 100 md5
 ip authentication key-chain eigrp 100 EIGRP-MD5
 duplex auto
 speed auto
!
router eigrp 100
 network 1.0.0.0
 network 12.0.0.0
 no auto-summary

R2#
!
key chain EIGRP-MD5
 key 1
   key-string MYPASS
!
interface Loopback0
 ip address 2.2.2.2 255.255.255.0
!
interface FastEthernet0/0
 ip address 12.1.1.2 255.255.255.0
 ip authentication mode eigrp 100 md5
 ip authentication key-chain eigrp 100 EIGRP-MD5
 duplex auto
 speed auto
!
router eigrp 100
 network 2.0.0.0
 network 12.0.0.0
 no auto-summary
!